electrical problems

I have a 92 cherokee. It will not start. I tryed two 92 XJ computers and it will not start. I put a 94 cherokee computer in and it started right up. I was told that i can't run the 94 computer, because it will mess things up. What is the difference that is letting the 94 start my jeep and the 92's not? thanks

Is it cranking and not starting, or not cranking at all? I don't see any reason you couldn't use the 94 computer as almost nothing changed engine-wise from 92. If it's an automatic, you will need to use the computer form another auto or the tranny will not shift properly.